Clutch.



No.- 849,69'7. PATENTBD APR. 9, 1907.

J. G. POTTER du J. JOHNSTON.

CLUTCH.

112110.11101: FILED 11111.17. 1902.

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UNITED STATES PATENT OFFICE.

JAMES C. POTTER AND JOHN JOHNSTON, OF PAWTUOKET, RHODE ISLAND, ASSIGNORS TO POTTER AND JOHNSTON MACHINE COMPANY, OF PAW- TUCKET, RHODEISLAND.

CLUTCH.

Specification of Letters Patent.

Patented April 9, 1907.

Application filed January 17, 1902. Serial No. 90,159.

To @ZZ whom, zit may concern:

Be it known that we, J AMES C. POTTER and JOHN JOHNSTON, of Pawtucket,in the county of Providence, and in the State of Ithode Island, haveinvented certain new and useful Improvements in Clutches; and we dohereby declare that the following is a full, clear, and exactdescription thereof, reference being had to the accompanying drawings,in which- Figure 1 is a vertical section of our clutch. Fig. 2 is across-section thereof on the line :c xof Fig. l. Figi 8 is across-section on the line y y of Fig. l and Fig. 4 is a detail view insection, showing the wedge operating mechanism.

Letters of like name and kind refer to like parts in each of thefigures.

The object of our invention is to provide a clutch of simple and cheapconstruction 5 and to this end our invention consists in the clutchhaving the features of construction substantially as hereinafterspecified and claimed.

In the embodiment of our invention which we have selected forillustration our clutch is shown adapted to connect either of twolatlie-spindle-driving mechanisms to the spindle; but it is to beunderstood that such embodiment of the invention is not to be consideredas in any wise exclusive, as we do not restrict ourselves to anyparticular relation in which to use the clutch or any particularadaptation of the parts thereof.

Describing such embodiment in detail, there are loosely mounted on thelathe-spindle A a cone-pulley B and a gear-wheel C, the latter beingdriven in a manner needless to be dcscribed. Fixed on the spindlebetween the pulley and the gear-wheel is a sleeve D, having at each endan annular flange E, one en circled by the pulley and the other by thegear-wheel or a flange thereon, but each of sufficiently less diameterthan the encircling portion of the respective part to leave a clearspace between. In the circumference of each flange E is an annulargroove, within which is seated a ring divided at two diametricallyopposite points and constituting two nearly-semicircular friction-shoesF and F, that are adapted to be expanded into contact with the adjacentencircling portion of the pulley or the gear-wheel, as the case may be.For expanding said shoes there is interposed between the adjacent endsthereof a tapering block or wedge G, the inner wider end of which isengaged by a screw Il in a l threaded radial opening in the sleeve D. At

its inner end the screw has fixed to it a pinion I, with which meshes arack K, by the reciprocation of which the pinion and the screw may berotated. The rack is preferably in the form of a round bar slabbed ofl",having the teeth where it is slabbed ofl, and it is placed in an openingin the sleeve D. A screw L, passing through a slot (Z in the sleeve D,connects the rack with a sliding collar M, encircling and splined to thesleeve, which is adapted to be moved in an axial direction by ahand-lever N in a well-known manner.

Between the ends of the shoes F and F, at a point diametrically oppositethe wedge G, is a taper block or wedge O, the larger end of which isengaged by the head of a screw I). Said screw P engages a threadedopening in a plug Q, that fills a radial opening that is provided forassembling the parts diainetrically opposite the opening in which theoperating screw II is placed. In line with the screw P the wedge O has aperforation o, and the pulley and gear-wheel have each a perforation inline with the screw P ofthe respective clutch, the object of saidperforations being to enable a screwahiver to be applied to the screw P.The wedge O is provided as a means of adjustment of the shoes F and F tocompensate for wear, and the screw P is a convenieiit means for movingthe wedge for such adjustment. The wedge-moving screw P is locked orheld by a lock-screw R, that impinges against the side thereof.

Preferably the shoes F and F are reduced in thickness intermediate theirextremities, and the wedge-engaging portions are inclined incorrespondence with the inclination of the wedges.

The operation of the clutch will be readily understood. By moving thecollar M in one direction the operating-screw Il will be revolved andthe wedge G moved outward, expanding the shoes F and F and pressing themagainst the pulley or gear-wheel surface, while by moving the collar inthc reverse direction the shoes F and F will contract and free orrelease the pulley or gear-wheel. In the particular adaptation oftheclutch which we have shown either the pulley or the gearwheel may beengaged or both disengaged by ICO stopping the collar M at anintermediate position. The clutch, as will be perfectly obvious, can beemployed for rotatively connecting one wheel or revoluble part andashaft or spindle, and we therefore do not limit ourselves to anarrangement such as that illustrated, wherein a double form is given theclutch to enable it to connect either of t'wo revoluble parts to a shaftor spindle.

Our clutch is of very simple construction, its parts being few, it canbe operated easily, and it does its work most efficiently.

Having thus described our invention, what we claim is- 1. In a clutch,the combination of independent unattached segment-form shoes, a surfacefor the latter to act on a wedge between separated ends of saidsegments, shoeoperating mechanism acting on said wedge to cause movementof the shoes in clutching and unclutching, a second wedge interposedbetween other separated ends of the segments, and mechanism acting onsaid second wedge, solely for adjustment of the shoes and independent ofthe shoe-operating mechanism, whereby it is operative independently ofthe latter and is not actuated when the shoeoperating mechanism isoperated.

2. In a clutch, the combination of a pair1 wedge, solely to causemovement of the shoes in clutching and unclutching, said mechanismcomprising a screw that engages the wedge, a pinion connected to thescrew, and a reciprocable rack, a second wedge interposed between saidshoes at another point of separation, and shoe-adjusting mechanismacting on the other wedge, solely for the purpose of adjustment andindependent of the shoe-operating mechanism, whereby it is operativeindependently of the latter and is not actuated when the shoe-operatingmechanism is operated.

In testimony that we claim the foregoing we have hereunto set our handsthis 31st day of August, A. I). 1901.

JAMES O. POTTER. JOHN JOHNSTON.

I/Vitnesses z JAMES L. JENKs, FLORENCE E. BATES.

